Acquire, characterize, catalogue, store, and distribute to investigators here and abroad a variety of human tumor cell lines having special utility for research in tumor diagnosis. Well characterized cell lines from solid tumors as well as from normal tissues have been included in the 1983 ATCC Catalog and are currently being distributed. Information concerning properties and utilities of these lines are provided to all interested investigators. Lines of highest distribution are being characterized further with regard to isoenzyme profiles, karyology, surface antigens, and so forth, as time and funds permit.